wiggins



July 13,1926.

D. H. waGGlNs TRANSMITTER FOR TELEPHONES AND THE LIKE na. Filed March 16 1923 ATTORNEYS the diaphragm is placed or secured. In this present invention said diaphragm is of special character. instead of being what is known as metal foil or gold toil, that is, a homogeneous sheet o'l metal, it is a compound sheet, consisting oi very thin gold leaf 221 secured by very thin adhesive material 222 to a very thin, strong, line silk fabric 22B. This fabric may be either cloth or paper, as desired. The compound diaphragm thus formed is as thin and flexible as the gold toil mentioned in the prior application, but it is superior to the gold foil on account of its greater' thinness and pliability, less elasticity and greater sensibility to soundv waves, whereby the minor tones are'4 clearly transmitted.

Inoperation, the current passes from the rear electrode through 'he carbon to the diaphragm sections and wire frame 2l and out through the ring 122. This distributes the current over the diaphragm so as not to be concentrated.

The diaphragm is held in place against the conducting ring 122 and the wire trame 2l by a.' wire or reticulated frame 28 which is placed against the aforesaid members so that the diaphragm will be held tightly in plac'e.

In front of what may be called the diaphragm construction, made ot'- the dia-v phragm4 and its holding means, such as the frames' 2l and 23 and-.the ring 122, there is placed a relatively thick ymat or layer 28y of' wool-like material; The wool-like material 28` is' preferably composed of' steel wool, but' it may be made ot other' wool or wool-like material. However, it is preterable and believed to be necessary tothe success'tul operation et the device that this'woollike material be substantially resilient, elastic and so that it will retain its position normally and be penetrated by the sound waves and yet not respond to them.' lt should be o'tsuch character as not' to mass against the sheet 01"" gold foil and prevent its freedom of vibration as would be the ease igt-'lit were composed of cotton or the like. The mat ofv steel'wool is 'held'preferably out ot direct engagement with the .O'old oil'by the inter- V'enngwire trame 2o, substantially as indicated in Figs. 4 and 5. y

The so'un'd waves pass through the. metal wool and beat against the diaphragm 22 and each section ol the diaphragm lying between-the `four wires of a small square net wire frame 21 thus becon es an independent andseparate diaphragm.

The foregoing' description and the associated drawings explain substantially the general features and construction oit thisisvention, although itis net limited to many of the particular' details Itherein set forth. It is ev-ident from what has' been said that the diaphragm will not vibrate as a whole and is so mounted and held that it is divided into a large number of relatively small diaphragm sections. Each of these sectional portions of the diaphragm is capable ot vibration under theA influence of the sound waves, and independently of the other seetions of the diaphragm.

By providing the transmitter with such similar and sensitive diaphragm sections, it

is enabled to be influenced by relatively since the minor tones are all reproduced, the

major tones are thereby relatively subordinated so that they are not so greatly emphasized as to cause a mere noise. ln tact, it is the minor tones that ena-ble different tenes or sounds to be distinguished and the loud major tones that cause the confusion ot sound in the ordinary telephonev and which render it diiiicult to distinguish the tones orsounds. Therefore', one ot' theimportanty results ofY this transmitter is the purity of tone it causes to be reproduced.

One result, it is believed, ofthe large' number oit very small sectional diaphragms of similar character andv action is the amplilication by them of the very minor tones, whereby in the repr'oducedtones or sounds, they have the same relative strength or character that the major and stronger minor tones have in the original tones or sound. This amplilication not only' results 'from the multiplicity ot the sectional diapliragins, but 1from the free' and sensitive movement ot each small diaphragm because ot the character of the diaphragm material.' This result is impossible where the diaphragm is made of a sheet of material that must be vibrated wholly or almost wholly and where there is much inertia and lag. rllhis sensitiveness prevents lag in the minor'tenes so that in the reproduced tones or sounds, the .ninor tones have the original position relative to the major tones in point et time as welll as in strength'.

rllhe nature and construction et this instrument enables it to be made o1" any size that may be required and desired for any use or situation. The ordinary transmitter cannot be made large. because the diaphragm would' become too heavy and the inertia thereo'l'y too great to be vibrated by the ordinary sound waves. Since, however, in this instrument the diaphragm is insmall lill) titi sections, they are substantially alike and the diaphragm as a Whole does not vibrate, the action is the same whether there would be a small or large number of diaphragm sections. lileuce, the instrument can be three .feet in diameter as well as three inches. '.llhe effe .t of enlargement is to increase the pou'er of the instrument and adapt it for use in conventions and for reproducing distant and delicate tones and particularly in connection with radio tele-phoning` and the like.

Another characteristic that a "very great energizing current may be used in connection with the instrument without the hissing and sizzling` noise heretofore asso-- ciated with the use of large currents. This is not only of value in ordinarylocal telephonina, but particularly in long distance work and in radio telephoning and the like.

The advantages of theI improved construction of transmitter over that described in my former application are first that the flexibility of the diaphragm is enormously increased, and there seems to be a total ab sence of elasticity With no decrease of the necessary electric conductivity.

This diaphragm is relatively much thinner than the the gold foil set forth in my former application and also much more pliable and light of Weight so that its resistance to sound waves is greatly reduced as compared With the gold foil, whereby it is rendered much more sensitive to the sound waves. lt is readily understood that a very thin silk fabric is much lighter of Weight and much more pliable than a body of gold, as in gold foil or any other metal foil, and the eidaremely thin and fragile character of gold leaf as compared With gold or metal foil is a matter of common knowledge. The advantage of usingr a. diaphragm of silk as a. basis is to enable the use of gold in its thin- .nest possible form and the relative thinness and lightness of zf rold leaf compared with gold foil is to some extent indicated by the cost of the tivo, the cost of the gold leaf beingv about tivo percent of the cost of the gold foil. The gold foil diaphragm is relan tively solid .metal and heavy and resisting),

` compared with the silk and gold leaf diaphragm, although. the gold foil diaphragm better than any rigid diaphragm in the combination set forth herein.

The invention claimed is:

l. ln a transmitter for telephonie instruments and the like, the combination of a diaphragm member formed of a fabric and metal leaf adhering throughout to and covering one side thereof, so that the diaphragm is conductive and a stationary backingr for the same, substantially as set forth.

ih ln a transmitter for telephonie instruments and the like, the combination of a diaphragm member consisting,1 of silk fabric and gold leaf adhering" to and covering one side thereof, and a stationary backing for the same, substantially as set forth.

3. lna transmitter for telephoniel instruments and the like, the combination of a (iliapbramn member having' a plurality of similar .'liapbragm sections, each formed of relatively thin fabric andA relatively thin metal leaf adhering to and covering` one side thereof, and a stationary backing` for the saine, substantially as set forth.

ln a transmitter for telephones and the like, the coml'iination of a diaphragm. member formed of relatively thin fabric and relatively thin metal leaf secured to and coif'eri g9`f one side thereof, and means for holding' the diaphragm member so as to sectionalize it into a plu ality of independently ifibratory dialihragm sections.

ln a transmitter for telephones and the like, the combination of a diaphragm member formed of relative-ly thin silk fabric and relativelyv thin gold leaf secured thereto and coi/*crinev one side thereof, and means for holding4 said. diaphragm member so as to sectionalize it into a plurality of independently vibratory diaphragm sections.

6. In a transmitter for telephones and the like, the combination of a thin pliable sheet as a diaphragm member thereof, said sheet having a metal surface, and a reticulated frame against which the diaphragm member is held so as to sectionalize it into a plurality of independently vibratory diaphragm members.

7. ln a transmitter for telephonie instruments and the like, the combination a carbon electrode, a stationary and reticul ated metal frame in front of said carbon electrode, said frame being insulated on the side thereof facing the carbon electrode and the other portions thereof beingconductive, a diaphragm member adjacent the front side of said frame, granular carbon between the carbon electrode and said frame and dia,.- phrag'm, and means for holding the diaphragm member against said frame so that the sections of the diaphragm member covering the openings in said frame will be independently vibratory, substantially as set forth.

8. In a transmitter for telephonie instruments and the like, the combination of a carbon electrode, a stationary and reticulated metal frame in front of said carbon electrode and the other portions thereof being conductive, said frame being insulated on the side thereof facing the carbon electrode, a diaphragm member adjacent the front side of said frame, granular carbon between the carbon electrode and said frame and diaiiihragm, and a conducting1 ring' for holding the margin of said diaphragm inember tigrlithr against .aid frame.

El., t emitter for telephonie iiis-trfoa llO ments and the lile, the combination of a carbon electrode, a stationary and reticulated metal frame in front of said carbon electrode and the other portions thereofbeing conductive, said frame being insulated on the side thereof facing the carbon electrode, a diaphragm member adjacent the front side of said frame, granular carbon between the carbon electrode and said frame and diaphragm, a conducting ring for holding the margin of said diaphragm member tightly against said frame, another reticu-a lated frame' in front of said diaphragm meinber and marginal conducting ring, and means for securing said elements together at their margin, substantially as shown.

l0. In a transmitter for telephonie instruments and the like, the combination ofv a carbon electrode, a stationary and reticulated metal frame in front of said carbon electrode and the other portions thereof being. conductive, said frame being insulated on the side thereof facing` the carbon electrode, a diaphragm member adjacent the front side of said frame, granular carbon betm'een'the carbon elect-rode and said frame and'diapliragm, a conducting ring for holding the margin of said diaphragm member tightly against said frame, and yielding means in front of the diaphragm for yieldingly holding it against said metal frame and permitting the sections thereof covering the opening in said frame to be independently vibratory.

1l. In a'transmitter for telephonie instruments and the like, the' combination of a carbon electrode, a stationary and reticulated metal frame in front of said carbon electrode and the other portions thereof being conductive, said frame being insulated on the side thereof facing the carbon eleotrode, a diaphragm member adjacent the front side of said frame, granular carbon between the carbon electrode and said frame and diaphragm, a conducting ring for holdingl the margin of said diaphragm member tightly against said frame, another reticulated' frame in front of said diaphragm member and marginal conducting ring, metal Wool in front of said front metal frame and engaging it andthe diaphragm member, and means for securing all of said elements tightly together at their margin.

ln Witness Wliereof,1'liave hereunto affixed my signature.r

DUDLEY HOV/TARD VIGGINS. 

